Their proxy license or requirements requires at least 400GB of disk space but the initial disk setup using the default OVF file will only create two disks - Disk 1 with 8GB and Disk 2 with 200GB.
Then Disk 1 disk size was increased to 200GB from 8GB and after this has been done, the warning message started to appear.
The default disk configuration which is "Disk 1 with 8GB and Disk 2 with 200GB" need to be maintained and in order to meet the requirement, an additional virtual disk need to be added. So the total disks will be Disk 1 with 8GB, Disk 2 with 200GB and Disk 3 with 200GB.